The Primary Breast Cancer Therapy Group (NSABP) is a multidisciplinary cooperative group consisting of surgeons, radiation therapists, medical oncologists and, at present, is conducting three major protocols. This institution has been a participant in this project since 1971. This grant application is being submitted for support of our institution's participation in the protocols conducted by the Primary Breast Cancer Therapy Group (NSABP) and should be considered with the Headquarters grant application submitted by the Project Chairman, Dr. Bernard Fisher. In addition to participating in Protocols 4, 5 and 7A, we have provided the Headquarters Office with samples of breast tumor for estrogen binding. We will collect blood samples for determination of biological markers. New protocols to evaluate segmental mastectomy, the use of immunopotentiating agent, C. parvum, and the use of other chemotherapeutic agents are in the final planning stages and should be implemented within the next few months for patients with Stage I and II breast cancer. A protocol for Stage III breast cancer patients is being finalized and should begin within the next few months. Extensive information has been obtained relative to the pathology specimens submitted by us from patients in Protocol No. 4